85 research outputs found

    Digital Reconstruction Supporting Investigation of Mishaps

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    In support of investigations of mishaps like the crash of the space shuttle Columbia, a process based on digital reconstruction from recovered components has been developed. The process is expected to reduce the need for physical reconstruction from recovered parts, reduce the time and cost of determining the cause of a mishap, and provide information useful in redesigning to prevent future mishaps. The process involves utilization of pre-existing techniques, hardware, and software to capture sizes and shapes of recovered parts in sets of digital data. The data are manipulated to enable rendering of captured geometric information by use of computer-aided design (CAD) and viewing software. The digitization of a part and study of its spatial relationship with other parts is taken to one of three levels of successively greater detail, depending on its importance to the investigation. The process includes a trajectory-analysis subprocess in which information from the digital reconstruction is combined with locations of recovered parts to reduce the area that must be searched to find other specified parts that have not yet been recovered. The digital product of the process is compatible with preexisting CAD and solid-model-rendering software

    School-based mental health intervention for children in war-affected Burundi: a cluster randomized trial

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    Background: Armed conflicts are associated with a wide range of impacts on the mental health of children and adolescents. We evaluated the effectiveness of a school-based intervention aimed at reducing symptoms of posttraumatic stress disorder, depression, and anxiety (treatment aim); and improving a sense of hope and functioning (preventive aim). Methods: We conducted a cluster randomized trial with 329 children in war-affected Burundi (aged 8 to 17 (mean 12.29 years, standard deviation 1.61); 48% girls). One group of children (n = 153) participated in a 15-session school-based intervention implemented by para-professionals, and the remaining 176 children formed a waitlist control condition. Outcomes were measured before, one week after, and three months after the intervention. Results: No main effects of the intervention were identified. However, longitudinal growth curve analyses showed six favorable and two unfavorable differences in trajectories between study conditions in interaction with several moderators. Children in the intervention condition living in larger households showed decreases on depressive symptoms and function impairment, and those living with both parents showed decreases on posttraumatic stress disorder and depressive symptoms. The groups of children in the waitlist condition showed increases in depressive symptoms. In addition, younger children and those with low levels of exposure to traumatic events in the intervention condition showed improvements on hope. Children in the waitlist condition who lived on their original or newly bought land showed improvements in hope and function impairment, whereas children in the intervention condition showed deterioration on these outcomes. Conclusions: Given inconsistent effects across studies, findings do not support this school-based intervention as a treatment for posttraumatic stress disorder and depressive symptoms in conflict-affected children. The intervention appears to have more consistent preventive benefits, but these effects are contingent upon individual (for example, age, gender) and contextual (for example, family functioning, state of conflict, displacement) variables. Results suggest the potential benefit of school-based preventive interventions particularly in post-conflict settings. Trial registration The study was registered as ISRCTN4228482

    Communications Biophysics

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    Contains reports on four research projects

    Temporal patterns of bat activity on the High Plains of Texas

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    Texas is home to more wind turbines and more bat species than any other state in the United States. Insectivorous bats provide an important economical ecosystem service in this region through agricultural pest regulation. Unfortunately, bats can be impacted negatively by wind turbines, and migratory bat species particularly so. To understand how bat activity changes throughout the year in western Texas, activity was monitored through echolocation calls and opportunistic mist-netting efforts over a period of four years (2012–2015). Peaks in activity were observed from March through April, and again in September, which coincides with previously documented migratory periods for many species native to the High Plains of Texas. Findings presented herein suggest that urban habitats are preferred stopover sites for migratory bat species while traversing arid regions such as those occurring in western Texas. In addition to human-made structures, urban habitats harbor non-native trees that provide suitable roost sites, aggregations of insect prey swarming outdoor light sources, and artificial water sources. It is important to understand bat activity in western Texas, not only for the benefit of agricultural pest suppression, but also to predict how the expansion of wind energy may affect bat populations in this region

    Communication Research

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    Contains reports on seven research projects.Carnegie Foundatio

    Communication Research

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    Contains reports on eight research projects.Bell Telephone Laboratories, IncorporatedCarnegie FoundationRockefeller FoundationOffice of Naval Researc

    Intravenous Aviptadil and Remdesivir for Treatment of COVID-19-Associated Hypoxaemic Respiratory Failure in the USA (Tesico): A Randomised, Placebo-Controlled Trial

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    BACKGROUND: There is a clinical need for therapeutics for COVID-19 patients with acute hypoxemic respiratory failure whose 60-day mortality remains at 30-50%. Aviptadil, a lung-protective neuropeptide, and remdesivir, a nucleotide prodrug of an adenosine analog, were compared with placebo among patients with COVID-19 acute hypoxaemic respiratory failure. METHODS: TESICO was a randomised trial of aviptadil and remdesivir versus placebo at 28 sites in the USA. Hospitalised adult patients were eligible for the study if they had acute hypoxaemic respiratory failure due to confirmed SARS-CoV-2 infection and were within 4 days of the onset of respiratory failure. Participants could be randomly assigned to both study treatments in a 2 × 2 factorial design or to just one of the agents. Participants were randomly assigned with a web-based application. For each site, randomisation was stratified by disease severity (high-flow nasal oxygen or non-invasive ventilation vs invasive mechanical ventilation or extracorporeal membrane oxygenation [ECMO]), and four strata were defined by remdesivir and aviptadil eligibility, as follows: (1) eligible for randomisation to aviptadil and remdesivir in the 2 × 2 factorial design; participants were equally randomly assigned (1:1:1:1) to intravenous aviptadil plus remdesivir, aviptadil plus remdesivir matched placebo, aviptadil matched placebo plus remdesvir, or aviptadil placebo plus remdesivir placebo; (2) eligible for randomisation to aviptadil only because remdesivir was started before randomisation; (3) eligible for randomisation to aviptadil only because remdesivir was contraindicated; and (4) eligible for randomisation to remdesivir only because aviptadil was contraindicated. For participants in strata 2-4, randomisation was 1:1 to the active agent or matched placebo. Aviptadil was administered as a daily 12-h infusion for 3 days, targeting 600 pmol/kg on infusion day 1, 1200 pmol/kg on day 2, and 1800 pmol/kg on day 3. Remdesivir was administered as a 200 mg loading dose, followed by 100 mg daily maintenance doses for up to a 10-day total course. For participants assigned to placebo for either agent, matched saline placebo was administered in identical volumes. For both treatment comparisons, the primary outcome, assessed at day 90, was a six-category ordinal outcome: (1) at home (defined as the type of residence before hospitalisation) and off oxygen (recovered) for at least 77 days, (2) at home and off oxygen for 49-76 days, (3) at home and off oxygen for 1-48 days, (4) not hospitalised but either on supplemental oxygen or not at home, (5) hospitalised or in hospice care, or (6) dead. Mortality up to day 90 was a key secondary outcome. The independent data and safety monitoring board recommended stopping the aviptadil trial on May 25, 2022, for futility. On June 9, 2022, the sponsor stopped the trial of remdesivir due to slow enrolment. The trial is registered with ClinicalTrials.gov, NCT04843761. FINDINGS: Between April 21, 2021, and May 24, 2022, we enrolled 473 participants in the study. For the aviptadil comparison, 471 participants were randomly assigned to aviptadil or matched placebo. The modified intention-to-treat population comprised 461 participants who received at least a partial infusion of aviptadil (231 participants) or aviptadil matched placebo (230 participants). For the remdesivir comparison, 87 participants were randomly assigned to remdesivir or matched placebo and all received some infusion of remdesivir (44 participants) or remdesivir matched placebo (43 participants). 85 participants were included in the modified intention-to-treat analyses for both agents (ie, those enrolled in the 2 x 2 factorial). For the aviptadil versus placebo comparison, the median age was 57 years (IQR 46-66), 178 (39%) of 461 participants were female, and 246 (53%) were Black, Hispanic, Asian or other (vs 215 [47%] White participants). 431 (94%) of 461 participants were in an intensive care unit at baseline, with 271 (59%) receiving high-flow nasal oxygen or non-invasive ventiliation, 185 (40%) receiving invasive mechanical ventilation, and five (1%) receiving ECMO. The odds ratio (OR) for being in a better category of the primary efficacy endpoint for aviptadil versus placebo at day 90, from a model stratified by baseline disease severity, was 1·11 (95% CI 0·80-1·55; p=0·54). Up to day 90, 86 participants in the aviptadil group and 83 in the placebo group died. The cumulative percentage who died up to day 90 was 38% in the aviptadil group and 36% in the placebo group (hazard ratio 1·04, 95% CI 0·77-1·41; p=0·78). The primary safety outcome of death, serious adverse events, organ failure, serious infection, or grade 3 or 4 adverse events up to day 5 occurred in 146 (63%) of 231 patients in the aviptadil group compared with 129 (56%) of 230 participants in the placebo group (OR 1·40, 95% CI 0·94-2·08; p=0·10). INTERPRETATION: Among patients with COVID-19-associated acute hypoxaemic respiratory failure, aviptadil did not significantly improve clinical outcomes up to day 90 when compared with placebo. The smaller than planned sample size for the remdesivir trial did not permit definitive conclusions regarding safety or efficacy. FUNDING: National Institutes of Health

    Dynamic networks and behavior: separating selection from influence.

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    A current problem in the analysis of behavioral dynamics, given a simultaneously evolving social network, is the difficulty of separating effects of partner selection from effects of social influence. In this paper we present a recently developed family of statistical models that enables researchers to separate the two effects in a statistically adequate manner. To illustrate our method we make use of a three-wave panel measured in the years 1995-1997 at a school in the West of Scotland. We are able to assess the strength of selection and influence mechanisms associated with friendship networks of substance-using adolescents
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